摘要:

AbstractThe sensitivity to hexobarbital was tested with an EEG‐threshold. Hexobarbital was infused continuously in a tail vein of male rats and the dose needed to obtain a burst suppression of 1 sec. or more in the EEG (the “silent second”) was determined. In the first part of the experiments the dose response and time response of the effect of physostigmine on the hexobarbital threshold was determined. The rats were pretreated with methylatropine 2.0 mg/kg subcutaneously. Testing of three different doses of physostigmine (0.5, 1.0 and 2.0 mg/kg intraperitoneally) showed that only the highest dose raised the hexobarbital threshold. The optimal time interval between the dose of physostigmine and hexobarbital threshold to obtain this effect was found to be around 1.5 hours. In the second part of the experiment the antagonistic effect of atropine was investigated. Methylatropine (2 mg/kg intraperitoneally) combined with physostigmine (2.0 mg/kg intraperitoneally) increased the hexobarbital threshold to 117 ± 4 per cent of a pre‐experimental value. Substitution of methylatropine with atropine (8 mg/kg intraperitoneally) gave a threshold value of 94 ± 4 per cent. Atropine combined with saline gave a threshold of 85 ± 2 per cent. The corresponding value after methylatropine was 100 ± 5 per cent. Thus pretreatment with atropine can reduce the increase in dose of hexobarbital caused by the CNS‐ effects of

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1977.tb02668.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractGuinea pigs were exposed to 1,1,2‐trichloroethane applied directly on the skin of the back for periods between 15 minutes and twelve hours under anaesthesia. Morphological changes could be observed in the epidermis after 15 minutes and continued to progress during continuing exposure. The changes consisted of pyknotic nuclei, perinuclear oedema of basal and suprabasilar cells as well as a focal separation of the epidermis from the corium with vesicle formations. The liver tissue showed reduction of glycogen content as well as hydropic changes in the centrilobular areas six hours after the start of exposure. The liver changes were less marked 12 hours after exposure and absent in non‐anaesthetized animals. No morphological changes were observed in the kidney or the br

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1977.tb02669.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractIt is known from experiments on rats and mice that control and polycyclic aromatic hydrocarbon‐induced activities of aryl hydrocarbon hydroxylase differ profoundly with regard to their inhibition by several compounds. In order to obtain information about the nature of the human enzyme system from different tissues, the inhibition of aryl hydrocarbon hydroxylase (AHH) by different compounds in the human foetal and adult liver, foetal adrenal gland, as well as the placenta was studied. Substantial AHH activity was present in all the livers and adrenal glands, but only in term placentas from smoking mothers. The placental AHH was inhibited by 7,8‐benzoflavone, but not appreciably by SKF 525 A, aminopyrine or metyrapone. On the other hand, the foetal liver AHH was inhibited by SKF 525A, aminopyrine and metyrapone, whereas 7,8‐benzoflavone apparently activated the enzyme. The adult human liver AHH resembled that of foetal liver. The foetal adrenal AHH displayed a pattern of inhibition differing from both the liver and the placenta. Maternal cigarette smoking did not have a substantial effect either on the enzyme activity or on the inhibitory properties. Foetal hepatic AHH resembled the enzyme from control‐rat liver and the placental AHH was similar to the enzyme from 3‐methylcholanthrene‐treated rat liver. The effect of 7,8‐benzoflavone on control rat liver AHH activity varied greatly from the prenatal to the adult period, whereas AHH activity in MC‐treated rat liver was always strongly inhibited by 7

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1977.tb02670.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

Clonal strains of rat pituitary tumour cells (GH3‐cells) synthesize and secrete prolactin into a chemically defined culture medium. Short time treatment (0.5–2 hrs) of cell cultures with noradrenaline (10‐3M) and dopamine (10‐3M) reduced the spontaneous secretion of prolactin by 50 % and 30 %, respectively, while pilocarpine (10‐3M) had no effect. Long‐term treatment (20 hrs) with noradrenaline (10‐3M) or with pilocarpine (10‐3M) inhibited prolactin synthesis by 45 % and 65 % of control cultures, respectively, Neither compounds affected cell growth. The inhibitory effect of noradrenaline, but not that of pilocarpine, was completely reversed 4 hrs after cessation of treatment. Adrenaline, dopamine and acetylcholine in concentrations up to 10‐3M did not change prolactin synthesis. In contrast thyroliberin treatment (2×10‐8M) caused a 45 % increase in prolactin secretion, and resulted in a 40 % increase in hormone synthesis after treatment for 20 hrs. It is concluded that both noradrenaline and dopamine are able to inhibit prolactin secretion. Prolactin synthesis could be inhibited by noradrenaline and pilocarpine. However, only the effect of noradrenaline is easily reversible on ce

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1977.tb02671.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractDiazoxide relaxed both polarized and depolarized rat uterus. The drug also counteracted the contractions elicited by Ca2+in a competitive manner. The relaxing effect was associated with an increase in the tissue level of cyclic AMP. This metabolic effect of diazoxide was inhibited by propranolol‐treatment and in preparations from reserpinized animals, while the mechanical effects were only partially reduced. Diazoxide was also found to increase the release of tritium from preparations preloaded with [3H]‐noradrenaline. It is suggested that diazoxide may induce some of its mechanical and metabolic effects by releasing the adrenergic transmittor substance noradrenaline. An effect of diazoxide on the Ca2+‐metabolism is also pro

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1977.tb02672.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractThe effects of amphetamine (A), 2‐, 3‐ and 4‐chloroamphetamine (CA), 4‐methylamphetamine (MA) and chlorphentermine (CP) in inhibiting the accumulation and in evoking release of radioactive labelled noradrenaline (NA), dopamine (DA) and 5‐hydroxytryptamine (5‐HT) and in inhibiting the oxidative deamination of tyramine and 5‐HT in mouse brain slices (midbrain and striatum) were examined. The inhibitory potencies on the NA uptakein vitroand after intraperitoneal administration varied only slightly, 3‐CA being the most potent and 2‐CA the least active compound. The structure activity for inhibition of the DA uptake in striatal slices was similar with the exception that CP was the least potent agent. The accumulation of 5‐HT was most potently inhibited by the 4‐ and 3‐substituted amphetamines. Only a small (20 %) fraction of the3H‐NA accumulated in the midbrain slices could be released by the amphetamines but a significant release was obtained at rather low concentrations (5 × 10‐7M). The release of radioactive DA and 5‐HT from striatal slices was much more pronounced and the orders of activities were similar to those for the inhibition of the accumulation of DA and 5‐HT, except that CP was comparatively less active in releasing 5‐HT. The oxidative deamination of tyramine and 5‐HT was most potently inhibited by 4‐CA and 4‐MA and this effect was obtained at the same doses producing inhibition of the amine uptake. No effect was obtai

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1977.tb02673.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractThe effects of the amphetamine derivatives (±)‐amphetamine (A), 2‐, 3‐ and 4‐chloroamphetamine (CA), 4‐methylamphetamine (MA) and chlorphentermine (CP) in producing central stimulation (increase in motor activity), antagonism of the reseipine syndrome, potentiation of 1‐dopa and 5‐hydroxy‐tryptophan (5HTP) responses in mice were investigated. The inhibitors of the membrane amine uptake desipramine (DMI) and chlorimipramine (CI) were also included in the study. It was found that the order in central stimulating potency was A>3‐CA = 4‐CA>MA>CP. 2‐CA, DMI and CI decreased the motor activity. All the compounds potentiated the 1‐dopa response with the order of activity: 4‐MA>A>2‐CA = 3‐CA = 4‐CA = CI ≥ DMI>CP. The decrease in motor activity (sedation) produced by reserpine was only reversed by A ≥ 3‐CA>2‐CA. α‐Methyltyrosine but not parachlorophenyl‐alanine, antagonized the reversal effect. Three of the compounds (3‐CA, 4‐CA and MA) produced head‐twitches in the reserpinized mice. The 5‐HTP syndrome was potentiated in order of potency by MA =

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1977.tb02674.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractPiflutixol, 6‐fluoro‐9‐[3‐(4‐(2‐hydroxyethyl)piperidino)propylidene]‐2‐trifluoromethyl‐thioxanthene, has been shown to have pronounced neuroleptic properties. It is a very potent inhibitor of methylphenidate‐induced stereotypies in mice, amphetamine‐ and apomorphine‐induced stereotypies in rats, apomorphine‐induced stereotypies and vomiting in dogs. Furthermore piflutixol causes cataleptic reaction in small doses and inhibits conditioned avoidance reaction in rats. The compound is equally potent orally and parenterally and has a prolonged effect. Piflutixol has up to the present proved to be the most potent inhibitor of dopamine‐stimulated adenylate cyclase in rat striatum in vitro. Piflutixol has a strong sedative effect (inhibition of spontaneous motor activity, induction of ptosis and potentiation of barbiturate anaesthesia) and in addition inhibits reticular arousal reaction in very low doses. Thus piflutixol constitutes a unique combination of potent anti‐stereotyped activity with potent sedative effects. This means that piflutixol may prove to be a low‐dose basic neurolept

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1977.tb02675.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractSeventeen food colours were tested as inhibitors of the simultaneous uptake of labelled o‐iodohippurate and iodipamide into slices of rat renal cortex. The results have been interpreted in terms of inhibition of two different anion‐transport systems: the hippurate or H‐system and the liver‐like L‐system. No clearcut relation was found between inhibition ability and system specificity on the one hand and molecular weight or structure on the other. However, most disulphonic azo dyes and quinoline yellow show an L‐system affinity while tri‐ and tetra‐sulphonic azo dyes, triarylmethanes and erytrosine show very little predilection for either of

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1977.tb02676.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

ISSN:0001-6683    

DOI:10.1111/j.1600-0773.1977.tb02677.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY